Gene expression analysis in the stomachs of water immersion-restraint stress rats using high-density oligonucleotide array.

Background And Aim: Research on gastric lesions developing in response to stress is essential to elucidating the pathogenesis of these lesions as well as the interplay with other factors, including Helicobacter pylori infection and non-steroidal anti-inflammatory drug use. Genes expressed individually or in sets, such as heat shock proteins, growth factors, proto-oncogenes and cyclooxygenases, have been investigated in the stomach. However, gene expression in the stomach after stress exposure have not yet been comprehensively examined. We investigated the gastric gene expression profile in response to stress.

Methods: A high-density oligonucleotide array, representing approximately 850 genes, was used to determine gene expression changes in the stomachs of water immersion-restraint stress (WIRS) rats.

Results: Fifty-eight genes including expressed sequence tag (EST) genes were upregulated more than twofold in the 30 min-WIRS rat stomach as compared with the control. Concomitantly, five genes were downregulated. Numbers of up- or downregulated genes decreased rapidly at 1 and 2 h of WIRS. Altered gene expression of heat shock proteins, cell cycle regulators, proto-oncogenes and metabolic enzymes were recognized. Several of these genes, including p38 mitogen-activated protein kinase, did not reportedly show gastric expression changes in response to stress.

Conclusion: These results suggest that, in addition to the previously identified stress-induced genes, expression of a number of other genes in the stomach is also involved in stress response.